What is the formula for calcium iodide

CaI₂

Calcium forms Ca²⁺ ions and iodine forms I⁻ ions. 1 Ca²⁺ ion combine with 2 I⁻ ions.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

let that person have a turn to speak : )